<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=y, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>运算符</title>
</head>
<body>
    <script>
        let num ="10";
        document.write(num-5+"<br>");
        document.write(num*5+"<br>");

        let num2 =10;
        document.write(num == num2);  // 比较值   true
        document.write(num === num2); // 先比较数据类型，在比较值  false
    </script>
</body>
</html>